(i) Field of the Invention
The present invention relates in general to blower housings used in furnaces to remove the products of combustion and particularly to the exhaust transition of the blower housing. The blower housing includes an integrally formed portion of the exhaust transition and is of a two-piece construction.
(ii) Description of the Related Art
Furnaces utilize a blower to induce a draft through the furnace to draw the heated air and the products of combustion through a heat exchanger and exhaust them through an exhaust pipe. The blower housings used in prior art furnaces are typically made of sheet metal and have an exhaust port that is rectangular. However, the exhaust pipe to which the blower exhaust port is to be connected is usually circular in cross-section. Therefore, to accomplish the transition from a rectangular exhaust port to a circular exhaust pipe inlet, a transition piece is attached to the blower housing that converts the rectangular exhaust port into a circular exhaust port that can be connected to the circular exhaust pipe. The transition piece has opposite first and second ends. The first end is rectangular and is adapted to be attached to the rectangular exhaust port on the blower housing. The second end is circular and is adapted to allow connection to a circular exhaust pipe.
The transition pieces are typically made of cast aluminum. Cast aluminum exhaust transition pieces are expensive to manufacture and increase the costs of the blower assembly and the associated furnace within which the blower assembly is utilized.
Additionally, the prior art exhaust transition pieces are often attached to the rectangular blower housing exhaust ports by screws. Usually, three or four sheet metal screws are used to attach an exhaust transition piece to the exhaust port of the blower housing. Because the exhaust transition piece is attached to the exhaust port for the blower housing by screws, the labor to attach the transition piece adds to the cost of the blower assembly. Furthermore, because the exhaust transition piece is only secured to the blower housing by three or four screws, the connection often becomes loose over time and the exhaust transition piece may rattle or produce undesirable noise when the blower is being run.
Therefore, what is needed is an exhaust transition piece that is less expensive to manufacture, less labor intensive to install, and reduces the possibility of rattling.